(a) No person shall allow any animal which he owns or which is in his custody or control to discharge any urine or fecal matter in any park, except curbed in park streets.

(b) Notwithstanding subdivision (a) of this section it shall be the further duty of each dog owner to immediately remove any fecal matter left by his dog in any park, including park street, and to assure that his dog does not urinate on or otherwise damage any tree or other plant in any park, or park street, including such trees or plants on the sidewalks and any area between the sidewalks and curbs of park streets.